I've never had a CS or IT/website problem with Priority Club.

I'm not a terribly active PC member - just an occasional stay, maybe 1-2 per year, but I find the program to be pretty good.

It's hard to drop a "quality" label on a program with such diverse brands. For an urban/resort stay, I'd probably look at the reviews of the specific Intercontinental Hotel in question vs. the nearby W, Renaissance, Marriott, etc. For a suburban stay, I've personally had good experiences with Staybridge - I think they stack up fine against Residence Inn in most places. For rural, I just look for whatever's newest - HI/HIX, Fairfield, or Hampton. The newness of the physical building seems to correlate fairly well with quality for a basic roadside motel. (Not to say that some older builds aren't well-maintained, but at least a new build is likely to have working power outlets, good HVAC, a tolerable mattress, etc.)

I think it might be a bit more difficult to be a "PC primary" guest if your main goal is urban business stays and then international or resort awards, simply because a lot of places only have one Intercontinental. I have had a lot of trips in my career where the "best" Marriott in a city is sold out or far from my price target, but there are usually other Marriotts to pick from.

The PC program is known around here for particularly good and frequent promotions... Whether it's ideal for you depends on where you tend to do paid stays and what your ideal rewards look like.